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Ian McColgin
01-30-2016, 06:41 AM
[IMc - This pop version doesn't even hint at the maths and I've some doubts that I could follow anyway, but it's fun to think about. And, no, it's not about time travel or even how that might happen.]

Scientists May Have Just Figured Out Why Time Moves Forward, Not Backwards

January 29, 2016 | by Alfredo Carpineti

Griffith University Associate Professor Joan Vaccaro has put forward a suggestion on why there’s a difference between the future and the past. According to her calculations, the laws of physics don’t have to distinguish between time and space, but since we don't experience time in the same way as space, something must make time different. And she thinks the answer is in a special class of quantum phenomena.

Certain quantum phenomena don’t behave in the same way if you’re going forward or backward in time, and she suggested that these are the key to understanding the arrow of time – the "asymmetry", or one-way direction, of time. And she said that in particular, subatomic particles known as K and B mesons could provide some interesting information. Her research is published in the Proceedings of The Royal Society A.

“If you want to know where the universe came from and where it’s going, you need to know about time,” Vaccaro said in a statement.

“Experiments on subatomic particles over the past 50 years show that nature doesn’t treat both directions of time equally. In particular, subatomic particles called K and B mesons behave slightly differently depending on the direction of time.”

Here's an analogy: If you leave a cup of coffee on the table you’d expect it to stay there. Sure, maybe you can move it around on the table, but it would still be a cup on a table. If the cup started flickering in and out of existence, you’d think something really weird was going on.

The flickering of the cup is not something we experience because it would violate the conservation of mass, but if space and time are truly two sides of the same coin, then it should be allowed to happen. And as an object is limited in space (got a size and a positin), they could also be limited in time (they could appear and disappear).

“In the connection between time and space, space is easier to understand because it’s simply there," she added. "But time is forever forcing us towards the future.

“Yet while we are indeed moving forward in time, there is also always some movement backwards, a kind of jiggling effect, and it is this movement I want to measure using these K and B mesons.”

Professor Vaccaro reworked the equations of quantum mechanics in a way that the conservation of mass wasn’t a given condition of the universe. She thus discovered that time and space did truly behave identically in that scenario. Even more interestingly, once violations of symmetries are allowed, the equations evolved into the ones that describe our universe and the law of conservation of mass arises organically from this theory.

“Understanding how time evolution comes about in this way opens up a whole new view on the fundamental nature of time itself," she said. "It may even help us to better understand bizarre ideas such as travelling back in time.”

http://www.iflscience.com/physics/new-explanation-why-time-moves-forward

Rigadog
01-30-2016, 10:25 AM
That was very interesting, what I could understand anyway...

Maybe it sheds some light on paranormal phenomena, like ghosts and aliens. Some ghosts appear to be like a recording, not interacting with the present but just repeating an action, unaware of us. Others seem to interact. In the case of the non-interacting spirit, have we have moved back in time(?). For the spirit that is responsive, is the spirit perhaps traveling forward in time? (If you don't believe in ghosts, this don't mean crap!).
As far as aliens are concerned, perhaps they are just us millions of years from now, traveling back in time, but still in the same place. An interesting book on the subject of UFO phenomena is "Close encounters of the Fourth Kind", by CDB Bryan (author of "Friendly Fire"). He writes as an open-minded skeptic. I put the book down feeling that the encounters are real, but that beings are not physically crossing vast areas of space. They may not be any more real than ghosts.

JimD
01-30-2016, 12:38 PM
Its nice to see some physicists and cosmologists taking a stab at new theories and models of how and what we experience as space and time might fundamentally be or be determined by. I've read mention of these mesons by other authors and anomalies seem like a good place to look.

isla
01-30-2016, 02:11 PM
Slight detour here, but I've often wondered about the potential for a sort of time travel using cryogenics i.e. you get frozen now and are revived in a couple of hundred years time. It would be a one-way ticket, but with recent advances in cryogenics it is likely to become possible.

Paul Pless
01-30-2016, 02:31 PM
Slight detour here, but I've often wondered about the potential for a sort of time travel using cryogenics i.e. you get frozen now and are revived in a couple of hundred years time. It would be a one-way ticket, but with recent advances in cryogenics it is likely to become possible.have you seen the documentary, Idiocracy?

Bobby of Tulsa
01-30-2016, 02:36 PM
A wrinkle in time.

isla
01-30-2016, 03:20 PM
have you seen the documentary, Idiocracy?

No, I had to look it up. Looks like fun. I love the Woody Allen film "Sleeper" which has a similar theme.

P.I. Stazzer-Newt
01-30-2016, 03:25 PM
Futurama?

PhaseLockedLoop
01-30-2016, 06:35 PM
there is no time behind us. time as we know it is nothing more than the rotation of the earth and the revolution of the planets around the sun. 1 day, 1 year. Light years are a unit of distance. Any thing observed in space is largely a measurement of lights ability to travel. when scientists say they are looking back in time to the beginnings of the universe, they are not observing events in real time, the are just watching the movie. Curvature of space, and wrinkles in time wormholes and such, are again in the realm of distances, not time. time goes forward only. you can't go back, when you get there, it's already gone.

damhik

Oh. Well, that settles it.

Vince Brennan
01-30-2016, 07:35 PM
Slight detour here, but I've often wondered about the potential for a sort of time travel using cryogenics i.e. you get frozen now and are revived in a couple of hundred years time. It would be a one-way ticket, but with recent advances in cryogenics it is likely to become possible.
Read "The Marching Morons" by Cyril Cornbluth. Quite old (1950's) but still apposite.

isla
01-30-2016, 08:02 PM
Then of course there is Stephen King's "The Langoliers" which are right behind you eating up the past so it no longer exists (or something). Which is so far removed from the OP that I can only apologise (sorry Ian).

Gerarddm
01-31-2016, 02:07 AM
I always thought time travel exists now. It is called memory.

Ian McColgin
01-31-2016, 08:05 AM
Gotta be careful about going too far in metaphysics from a model. Feinman once famously developed a formula for the mass and velocity and path and position and so on that explained subatomic particles where the only difference was the value of time, from -xT to +xT. He then added to the model a six dimensional space-time grid and showed that our experience of time is rather like (think three dimensions of time for a moment) being on a string looped along. We understand our freedom to move in the three dimensions of space but we don't know how to move consciously around in the three dimensions of space. Anyway, get your head around that and remember the -xT to +xT and consider the infinity of it all . . . The material universe as we experience it is just the one particle showing up where we happen to be roaring through at infinitely many different T values . . .

It's a joke. Don't get all mystical. Just as in the Ptolomeic universe, the "crystal spheres" were not "actually" there and certainly were not "actually" crystal. Even good practical scientists get confused on the boundary of critical realism as to just what the metaphysical status of mathematical models might really be.

Ian McColgin
01-31-2016, 08:47 AM
There's a difference between making a joke to make a metaphysical point and scoffing at important discoveries or scientific revolutions.

Jim Mahan
01-31-2016, 09:19 AM
Clearly, time travel from the future to the past is impossible. If it weren't impossible, due to the infinite nature of the future, there would have to be, eventually, someone from some time in the future with such a time machine, who wanted to travel back to our time. Also clearly, I think, were that to happen, it would be obvious, given the human propensity for scrutinizing the past and our ancestors, and since we haven't ever noticed such a thing, it can only mean that it just can't happen.

If one could travel backwards in time, someone would surely already have done so. The natural thing would be to go back a century farther than your target date, put a dime down on one sure thing after another, then pop ahead a hundred years when the compound interest would create billions for your scions. One would go to San Francisco in the 1830s and buy up all the bayside property, pop up to later in the same century and buy up all the railroad right of ways, and all the stock in railroad companies, and continue to win bets on every baseball and football playoff game played in any year.

JimD
01-31-2016, 04:33 PM
Clearly, time travel from the future to the past is impossible. If it weren't impossible, due to the infinite nature of the future, there would have to be, eventually, someone from some time in the future with such a time machine, who wanted to travel back to our time. Also clearly, I think, were that to happen, it would be obvious, given the human propensity for scrutinizing the past and our ancestors, and since we haven't ever noticed such a thing, it can only mean that it just can't happen.

If one could travel backwards in time, someone would surely already have done so. The natural thing would be to go back a century farther than your target date, put a dime down on one sure thing after another, then pop ahead a hundred years when the compound interest would create billions for your scions. One would go to San Francisco in the 1830s and buy up all the bayside property, pop up to later in the same century and buy up all the railroad right of ways, and all the stock in railroad companies, and continue to win bets on every baseball and football playoff game played in any year.

I don't quite share your clarity of vision. But an HG Wells sci-fi conception of time as a sort of cosmic medium that we freely move through or that carries us forward as free willed agents and given the right gizmo could point and click our cursors into the past and rewrite events is so far as I know the least favoured idea among physicists, philosophers, and cosmologists seriously trying to figure out what the word time might actually mean.

Daniel Noyes
02-01-2016, 02:03 PM
Clearly, time travel from the future to the past is impossible. If it weren't impossible, due to the infinite nature of the future, there would have to be, eventually, someone from some time in the future with such a time machine, who wanted to travel back to our time. Also clearly, I think, were that to happen, it would be obvious, given the human propensity for scrutinizing the past and our ancestors, and since we haven't ever noticed such a thing, it can only mean that it just can't happen.

If one could travel backwards in time, someone would surely already have done so. The natural thing would be to go back a century farther than your target date, put a dime down on one sure thing after another, then pop ahead a hundred years when the compound interest would create billions for your scions. One would go to San Francisco in the 1830s and buy up all the bayside property, pop up to later in the same century and buy up all the railroad right of ways, and all the stock in railroad companies, and continue to win bets on every baseball and football playoff game played in any year.

If you could send a message, or even a very simple binary code or signal back in time only a few munites... you could become the richest man on earth by tradeing stocks, bonds etc.

very dangerous stuff

JimD
02-01-2016, 02:31 PM
A related article on quantum time. Not quite a fundamental description but a new description of the 'units' of time. This quote hints at my personal favourite idea of time as an aspect of conscious experience. What's new here is the possibility that bits of time are much bigger than Planck scale.


"The physical universe is really like a movie/motion picture, in which a series of still images shown on a screen creates the illusion of moving images," Faizal said. "Thus, if this view is taken seriously, then our conscious precipitation of physical reality based on continuous motion becomes an illusion produced by a discrete underlying mathematical structure."

Read more at: http://phys.org/news/2016-02-physicists-implications-quantum-mechanics-philosophy.html#jCp http://phys.org/news/2016-02-physicists-implications-quantum-mechanics-philosophy.html

willmarsh3
02-01-2016, 04:22 PM
have you seen the documentary, Idiocracy?

I saw that movie a while back. It was quite interesting on showing a future that is entirely possible and maybe even likely.

I also watched "The Langoliers" which posits that time doesn't exist more than a short while ahead or behind.

Breakaway
02-01-2016, 04:36 PM
Stephen King explored some time-space shifting concepts in his novels. In particular, The Regulators, The Mist and The Dark Tower series come to mind. Simply put, action occurring in a different time tears through,or bleeds through, to the present.

Not that King's work is scientific, but having read some quantum physics, as well as King, I believe some of his work to have been influenced by the concept of spacetime,etc. As such, these works may offer a means to help intuit the actual science.

Kevin